中国环境科学

作者：王诗生, 杨玉, 盛广宏, 刘轶鋆, 李申波

单位：1. 安徽工业大学能源与环境学院, 安徽 马鞍山 243002;2. 安徽工业大学生物膜法水质净化及利用技术教育部工程研究中心, 安徽 马鞍山 243032

关键词：盐酸四环素,磁性生物炭,氧化改性,密度泛函理论,反应机理

基金：教育部工程研究中心开放基金资助项目(BWPU2021KF07,BWPU2021ZY02);安徽省大学生创新创业训练项目(S202310360400)

Tetracycline hydrochloride (TC) degradation was investigated utilizing hydrogen peroxide modified magnetic biochar (H2O2modified biochar, HMB) as an activator of peroxydisulfate (PDS), with a focus on assessing the impact of initial pH on TC degradation kinetics. The underlying reaction mechanisms and degradation pathways of HMB-activated PDS for TC degradation were elucidated through a series of experimental techniques, including quenching tests, electron paramagnetic resonance (EPR) spectroscopy for identifying active species, X-ray photoelectron spectroscopy (XPS) analysis, density functional theory (DFT) calculations, and liquid-liquid mass spectrometry (LC-MS) detection. Hydrogen peroxide modification significantly enhanced TC removal, achieving a removal rate of 83.9% under the specified conditions of TC concentration (20mg/L), PDS concentration (1mmol/L), and HMB dosage (0.5g/L). This efficacy surpassed that of PDS alone or the unmodified biochar system, albeit exhibiting a decrease in removal efficiency with rising pH levels. Quenching tests and EPR analyses unveiled both radical and non-radical pathways contributing to TC degradation, the active species mainly includes: SO4.-、·OH、O2.-and 1O2. XPS analysis identified carbonyl (C=O) functionalities as the primary active sites responsible for TC degradation within the HMB/PDS system. Complementary DFT calculations were employed to quantitatively assess the contribution of C=O moieties to the HMB/PDS-mediated degradation process. Furthermore, LC-MS analyses coupled with DFT calculations delineated two distinct degradation pathways for TC, involving mechanisms such as deamidation, hydroxylation, demethylation, and dehydration ring opening.

来源：2024年第11期

《中国环境科学》期刊编辑部

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